First-principles study on the formation energies of Ga₁-_xCr_xAs

The electronic structure and formation energy of the Ga_1-xCr_xAs compound has been studied by principles of methods based on the Density Functional Theory. The formation energy of the compound is calculated, as well as the vacancies and substitutions. The equations of Kohn-Sham are solved employing the plane wave method and the ultra-soft atomic pseudopotentials approximation. The generalized gradient approximation was employed for the exchange and correlation energy in the Perdew-Burke-Ernzerhof (PBE) parametrization as it is implemented in the computational code Quantum Espresso. It was found that the most favourable configuration is the GaAs lattice by doing the substitution of one Ga atom by one Cr in the analyzed lattices. (paper)